Subject: Protocol Action: 0-byte Support for R-mode in Link-Layer Assisted ROHC Profile to Proposed Standard

From: The IESG <[email-masked]>
Date: Tue, 10 Sep 2002 10:56:36 -0400

The IESG has approved the Internet-Draft '0-byte Support for R-mode in
Link-Layer Assisted ROHC Profile'
<draft-ietf-rohc-rtp-lla-r-mode-02.txt> as a Proposed Standard.

The IESG also approved publication of Lower Layer Guidelines for Robust
RTP/UDP/IP Header Compression
<draft-ietf-rohc-rtp-lower-layer-guidelines-03.txt> as an Informational
RFC.

These documents are the product of the Robust Header Compression
Working Group.  The IESG contact persons are Allison Mankin and Scott
Bradner.

Technical Summary

  The "0-byte Support for R-mode in Extended Link-Layer Assisted RObust
  Header Compression Profile" defines an additional mode of the profile
  defined in "A Link-Layer Assisted ROHC Profile for IP/UDP/RTP" (now in
  the RFC Editor's queue). That document specified zero-byte header
  compression in order to avoid the single octet ROHC header in certain
  older air interfaces from pushing a packet voice stream into the next
  higher fixed packet size for the radio. The former document defined
  the zero-byte operation for Unidirectional and Optimistic modes only
  (U-mode and O-mode), but Reliable Bidirectional mode (R-mode) required
  additional work. This specification completes the Link-Layer Assisted
  0-byte profile with R-mode, with the result that the majority of
  ROHC RTP packets can be sent out (on radio links with the defined
  characteristics) with a header-free packet format during normal 
  operation.
   
  The "Lower Layer Guidelines for Robust RTP/UDP/IP Header Compression"
  document describes requirements that RObust Header Compression puts on
  lower layers, especially aimed at those who are engineering and 
  deploying emerging radio systems such as those specified by 3GPP, 
  3GPP2, ETSI, etc, to simplify incorporation of ROHC technology, and 
  limit the amount of detail about the ROHC algorithms and protocols 
  that need to be understood by link layer designers or engineers. Both 
  general guidelines and guidelines specific for cellular systems are 
  provided.

Working Group Summary
 
  The working group supported the publication of both of these
  documents.
 
Protocol Quality

  These documents were reviewed for the IESG by Allison Mankin.
  As noted, the Reliable-Mode specification was held in the WG
  for extra rounds of review, and the working group and IETF
  Last Calls did not raise issues.